| Message ID | 20230322104639.221402-1-treapking@chromium.org |
|---|---|
| Headers | show |
| Series | Register Type-C mode-switch in DP bridge endpoints | expand |
On Wed, Mar 22, 2023 at 06:46:32PM +0800, Pin-yen Lin wrote: > Add helpers to register and unregister Type-C "switches" for bridges > capable of switching their output between two downstream devices. > > The helper registers USB Type-C mode switches when the "mode-switch" > and the "reg" properties are available in Device Tree. ... > +config DRM_DISPLAY_DP_TYPEC_HELPER > + bool > + default y def_bool y > + depends on DRM_DISPLAY_HELPER > + depends on DRM_DISPLAY_HELPER=TYPEC || TYPEC=y > + help > + DRM display helpers for USB Type-C Displayport Alternate mode. Hmm... Dunno if this help is enough. ... > + snprintf(name, sizeof(name), "%pfwP-%u", fwnode, port_num); Would it be possible to have a dup in name and would it be a problem if so? ... > +/** > + * drm_dp_register_typec_switches() - register Type-C switches > + * @dev: Device that registers Type-C switches > + * @port: Device node for the switch > + * @switch_desc: A Type-C switch descriptor > + * @data: Private data for the switches > + * @mux_set: Callback function for typec_mux_set > + * > + * This function registers USB Type-C switches for DP bridges that can switch > + * the output signal between their output pins. This function uses devm_kcalloc > + * to allocate memory, so it is expected to only call this in the driver probe > + * functions. > + * > + * Currently only mode switches are implemented, and the function assumes the > + * given @port device node has endpoints with "mode-switch" property. > + * The port number is determined by the "reg" property of the endpoint. `kernel-doc -v ...` should complain on absence of "Return" section. > + */ ... > + switch_desc->typec_ports = devm_kcalloc(dev, switch_desc->num_typec_switches, > + sizeof(struct drm_dp_typec_port_data), sizeof(*switch_desc_typec_ports), ? > + GFP_KERNEL); > + if (!switch_desc->typec_ports) > + return -ENOMEM; ... > +#ifdef CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER Ah, maybe this should use IS_REACHABLE() ? > +void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc); > +int drm_dp_register_typec_switches(struct device *dev, struct fwnode_handle *port, > + struct drm_dp_typec_switch_desc *switch_desc, > + void *data, typec_mux_set_fn_t mux_set); > +#else > +static inline void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc) > +{ > +} > +static inline int drm_dp_register_typec_switches( > + struct device *dev, struct fwnode_handle *port, > + struct drm_dp_typec_switch_desc *switch_desc, void *data, > + typec_mux_set_fn_t mux_set) > +{ > + return -EOPNOTSUPP; > +} > +#endif
On Wed, Mar 22, 2023 at 06:46:36PM +0800, Pin-yen Lin wrote: > Register USB Type-C mode switches when the "mode-switch" property and > relevant ports are available in Device Tree. Configure the crosspoint > switch based on the entered alternate mode for a specific Type-C > connector. > > Crosspoint switch can also be used for switching the output signal for > different orientations of a single USB Type-C connector, but the > orientation switch is not implemented yet. A TODO is added for this. ... > +static int anx7625_typec_mux_set(struct typec_mux_dev *mux, > + struct typec_mux_state *state) > +{ > + struct drm_dp_typec_port_data *port = typec_mux_get_drvdata(mux); > + struct anx7625_data *ctx = port->data; > + struct device *dev = ctx->dev; > + struct drm_dp_typec_switch_desc switch_desc = ctx->switch_desc; > + bool new_dp_connected, old_dp_connected; > + > + if (switch_desc.num_typec_switches == 1) > + return 0; > + wait_for_completion(&ctx->mux_register); How do we guarantee this won't become an infinite waiting? Perhaps a comment explaining that? > + old_dp_connected = ctx->port_data[0].dp_connected || > + ctx->port_data[1].dp_connected; > + > + ctx->port_data[port->port_num].dp_connected = > + state->alt && > + state->alt->svid == USB_TYPEC_DP_SID && > + state->alt->mode == USB_TYPEC_DP_MODE; > + > + dev_dbg(dev, "mux_set dp_connected: c0=%d, c1=%d\n", > + ctx->port_data[0].dp_connected, ctx->port_data[1].dp_connected); > + > + new_dp_connected = ctx->port_data[0].dp_connected || > + ctx->port_data[1].dp_connected; > + > + /* DP on, power on first */ > + if (!old_dp_connected && new_dp_connected) > + pm_runtime_get_sync(dev); > + > + anx7625_typec_two_ports_update(ctx); > + > + /* DP off, power off last */ > + if (old_dp_connected && !new_dp_connected) > + pm_runtime_put_sync(dev); > + > + return 0; > +} ... > + struct device_node *port_node = of_graph_get_port_by_id(dev->of_node, 1); You use fwnode below, so why not fwnode_graph_...(dev_fwnode(dev), ...) ? > + struct drm_dp_typec_switch_desc *switch_desc = &ctx->switch_desc; > + int ret; > + u32 dp_lanes[4]; > + unsigned int i, num_lanes; > + > + /* > + * Currently, only mode switch is implemented. > + * TODO: Implement Type-C orientation switch for anx7625. > + */ > + ret = drm_dp_register_typec_switches(dev, &port_node->fwnode, > + &ctx->switch_desc, ctx, > + anx7625_typec_mux_set); > + if (ret) > + return ret; > + > + ctx->port_data = devm_kcalloc(dev, switch_desc->num_typec_switches, > + sizeof(struct anx7625_typec_port_data), sizeof(*ctx->port_data), ? > + GFP_KERNEL); > + if (!ctx->port_data) { > + ret = -ENOMEM; > + goto unregister_mux; > + } ... > +struct anx7625_typec_port_data { > + bool dp_connected; > + enum typec_orientation orientation; Most likely enum will be 32-bit and bool 8-bit. Which means that the data type size become 8 bytes for no reason. Can you swap the lines and perhaps check this with `pahole` tool? > +};
Il 22/03/23 11:46, Pin-yen Lin ha scritto: > These two drivers embed a i2c_client in their private driver data, but > only strict device is actually needed. Replace the i2c_client reference > with a struct device one. > > Signed-off-by: Pin-yen Lin <treapking@chromium.org> > Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Il 22/03/23 11:46, Pin-yen Lin ha scritto: > The output port endpoints can be connected to USB-C connectors. > Running drm_of_find_panel_or_bridge() with such endpoints leads to > a continuous return value of -EPROBE_DEFER, even though there is > no panel present. > > To avoid this, check for the existence of a "mode-switch" property in > the port endpoint, and skip panel registration completely if so. > > Signed-off-by: Pin-yen Lin <treapking@chromium.org> > Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Il 22/03/23 11:46, Pin-yen Lin ha scritto: > From: Prashant Malani <pmalani@chromium.org> > > When using OF graph, the fw_devlink code will create links between the > individual port driver (cros-ec-typec here) and the parent device for > a Type-C switch (like mode-switch). Since the mode-switch will in turn > have the usb-c-connector (i.e the child of the port driver) as a > supplier, fw_devlink will not be able to resolve the cyclic dependency > correctly. > > As a result, the mode-switch driver probe() never runs, so mode-switches > are never registered. Because of that, the port driver probe constantly > fails with -EPROBE_DEFER, because the Type-C connector class requires all > switch devices to be registered prior to port registration. > > To break this deadlock and allow the mode-switch registration to occur, > purge all the usb-c-connector nodes' absent suppliers. This eliminates > the connector as a supplier for a switch and allows it to be probed. > > Signed-off-by: Prashant Malani <pmalani@chromium.org> > Signed-off-by: Pin-yen Lin <treapking@chromium.org> > Reviewed-by: Chen-Yu Tsai <wenst@chromium.org> > Tested-by: Chen-Yu Tsai <wenst@chromium.org> > Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
On Wed, Mar 22, 2023 at 06:46:39PM +0800, Pin-yen Lin wrote: > Register USB Type-C mode switches when the "mode-switch" property and > relevant port are available in Device Tree. Configure the "lane_swap" > state based on the entered alternate mode for a specific Type-C > connector, which ends up updating the lane swap registers of the it6505 > chip. ... > + struct device_node *port_node = of_graph_get_port_by_id(dev->of_node, 1); > + struct drm_dp_typec_switch_desc *switch_desc = &it6505->switch_desc; > + int ret; > + u32 dp_lanes[4]; > + unsigned int i, num_lanes; > + > + ret = drm_dp_register_typec_switches(dev, &port_node->fwnode, > + &it6505->switch_desc, it6505, > + it6505_typec_mux_set); > + if (ret) > + return ret; > + > + it6505->port_data = devm_kcalloc(dev, switch_desc->num_typec_switches, > + sizeof(struct it6505_typec_port_data), > + GFP_KERNEL); > + if (!it6505->port_data) { > + ret = -ENOMEM; > + goto unregister_mux; > + } A couple of the similar comments as per previous similar patch. ... > /* get extcon device from DTS */ > extcon = extcon_get_edev_by_phandle(dev, 0); > - if (PTR_ERR(extcon) == -EPROBE_DEFER) > - return -EPROBE_DEFER; > - if (IS_ERR(extcon)) { > - dev_err(dev, "can not get extcon device!"); > - return PTR_ERR(extcon); > + ret = PTR_ERR_OR_ZERO(extcon); > + if (ret == -EPROBE_DEFER) > + return ret; > + Unnecessary blank line. > + if (ret) { > + if (ret != -ENODEV) > + dev_warn(dev, "Cannot get extcon device: %d\n", ret); > + > + it6505->extcon = NULL; > + } else { > + it6505->extcon = extcon; ... > + ret = it6505_register_typec_switches(dev, it6505); > + if (ret != -ENODEV) > + dev_warn(dev, "Didn't register Type-C switches, err: %d\n", ret); > + Unnecessary blank line. > + if (ret && !it6505->extcon) { > + dev_err(dev, "Both extcon and Type-C switch are not registered.\n"); > + return -EINVAL; Why not return ret here? > + }
On Wed, 22 Mar 2023, Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote: > On Wed, Mar 22, 2023 at 06:46:32PM +0800, Pin-yen Lin wrote: >> +#ifdef CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER > > Ah, maybe this should use IS_REACHABLE() ? Personally, I think IS_REACHABLE() is a build-time band-aid solution to a problem that should be solved in Kconfig. :p I think it always means there's a configuration combo that shouldn't exist, and it's a surprise to the user when they've configured something, Kconfig has deemed it a valid configuration, but they don't get the feature they want. As a user, how would they even debug that case? Double check configs, don't see anything wrong. BR, Jani.
On Wed, 22 Mar 2023 at 12:47, Pin-yen Lin <treapking@chromium.org> wrote: > > Add helpers to register and unregister Type-C "switches" for bridges > capable of switching their output between two downstream devices. > > The helper registers USB Type-C mode switches when the "mode-switch" > and the "reg" properties are available in Device Tree. > > Signed-off-by: Pin-yen Lin <treapking@chromium.org> > > --- > > Changes in v14: > - Introduce a new Kconfig becuase it didn't build when CONFIG_TYPEC=m > - Add comments about devm_* usage > - Fix style issues > > Changes in v13: > - Add typec_mode_switch_node_count helper > - Fix style issues > > Changes in v12: > - Add fwnode_for_each_typec_mode_switch macro > - Remove a duplicated dmesg in the helper > - Used IS_REACHABLE instead to guard the function signatures > > Changes in v11: > - Use fwnode helpers instead of DT > - Moved the helpers to a new file > - Use "reg" instead of "data-lanes" to determine the port number > - Dropped collected tags due to new changes > > Changes in v10: > - Collected Reviewed-by and Tested-by tags > - Replaced "void *" with "typec_mux_set_fn_t" for mux_set callbacks > - Print out the node name when errors on parsing DT > - Use dev_dbg instead of dev_warn when no Type-C switch nodes available > - Made the return path of drm_dp_register_mode_switch clearer > > Changes in v8: > - Fixed the build issue when CONFIG_TYPEC=m > - Fixed some style issues > > Changes in v7: > - Extracted the common codes to a helper function > - New in v7 > > drivers/gpu/drm/display/Kconfig | 8 ++ > drivers/gpu/drm/display/Makefile | 2 + > drivers/gpu/drm/display/drm_dp_typec_helper.c | 105 ++++++++++++++++++ > include/drm/display/drm_dp_helper.h | 46 ++++++++ > 4 files changed, 161 insertions(+) > create mode 100644 drivers/gpu/drm/display/drm_dp_typec_helper.c > > diff --git a/drivers/gpu/drm/display/Kconfig b/drivers/gpu/drm/display/Kconfig > index 09712b88a5b8..d61076947a1c 100644 > --- a/drivers/gpu/drm/display/Kconfig > +++ b/drivers/gpu/drm/display/Kconfig > @@ -29,6 +29,14 @@ config DRM_DISPLAY_HDMI_HELPER > help > DRM display helpers for HDMI. > > +config DRM_DISPLAY_DP_TYPEC_HELPER > + bool > + default y > + depends on DRM_DISPLAY_HELPER > + depends on DRM_DISPLAY_HELPER=TYPEC || TYPEC=y If it is a select'able option, it doesn't make sense to use "depends" here. Select will override depends. > + help > + DRM display helpers for USB Type-C Displayport Alternate mode. > + > config DRM_DP_AUX_CHARDEV > bool "DRM DP AUX Interface" > depends on DRM && DRM_DISPLAY_HELPER > diff --git a/drivers/gpu/drm/display/Makefile b/drivers/gpu/drm/display/Makefile > index 17ac4a1006a8..2202a6aea38e 100644 > --- a/drivers/gpu/drm/display/Makefile > +++ b/drivers/gpu/drm/display/Makefile > @@ -8,6 +8,8 @@ drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_HELPER) += \ > drm_dp_helper.o \ > drm_dp_mst_topology.o \ > drm_dsc_helper.o > +drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER) += \ > + drm_dp_typec_helper.o > drm_display_helper-$(CONFIG_DRM_DISPLAY_HDCP_HELPER) += drm_hdcp_helper.o > drm_display_helper-$(CONFIG_DRM_DISPLAY_HDMI_HELPER) += \ > drm_hdmi_helper.o \ > diff --git a/drivers/gpu/drm/display/drm_dp_typec_helper.c b/drivers/gpu/drm/display/drm_dp_typec_helper.c > new file mode 100644 > index 000000000000..1562a9ccdaf2 > --- /dev/null > +++ b/drivers/gpu/drm/display/drm_dp_typec_helper.c > @@ -0,0 +1,105 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include <linux/usb/typec_mux.h> > +#include <drm/display/drm_dp_helper.h> > + > +static int drm_dp_register_mode_switch(struct device *dev, > + struct fwnode_handle *fwnode, > + struct drm_dp_typec_switch_desc *switch_desc, > + void *data, typec_mux_set_fn_t mux_set) > +{ > + struct drm_dp_typec_port_data *port_data; > + struct typec_mux_desc mux_desc = {}; > + char name[32]; Why 32? > + u32 port_num; > + int ret; > + > + ret = fwnode_property_read_u32(fwnode, "reg", &port_num); > + if (ret) { > + dev_err(dev, "Failed to read reg property: %d\n", ret); > + return ret; > + } > + > + port_data = &switch_desc->typec_ports[port_num]; > + port_data->data = data; > + port_data->port_num = port_num; > + port_data->fwnode = fwnode; > + mux_desc.fwnode = fwnode; > + mux_desc.drvdata = port_data; > + snprintf(name, sizeof(name), "%pfwP-%u", fwnode, port_num); I think it makes more sense to use dev_name here instead of fwnode. > + mux_desc.name = name; > + mux_desc.set = mux_set; > + > + port_data->typec_mux = typec_mux_register(dev, &mux_desc); > + ret = PTR_ERR_OR_ZERO(port_data->typec_mux); > + if (ret) > + dev_err(dev, "Mode switch register for port %d failed: %d\n", > + port_num, ret); > + > + return ret; > +} > + > +/** > + * drm_dp_register_typec_switches() - register Type-C switches > + * @dev: Device that registers Type-C switches > + * @port: Device node for the switch > + * @switch_desc: A Type-C switch descriptor > + * @data: Private data for the switches > + * @mux_set: Callback function for typec_mux_set > + * > + * This function registers USB Type-C switches for DP bridges that can switch > + * the output signal between their output pins. This function uses devm_kcalloc > + * to allocate memory, so it is expected to only call this in the driver probe > + * functions. > + * > + * Currently only mode switches are implemented, and the function assumes the > + * given @port device node has endpoints with "mode-switch" property. > + * The port number is determined by the "reg" property of the endpoint. > + */ > +int drm_dp_register_typec_switches(struct device *dev, struct fwnode_handle *port, > + struct drm_dp_typec_switch_desc *switch_desc, > + void *data, typec_mux_set_fn_t mux_set) > +{ > + struct fwnode_handle *sw; > + int ret; > + > + switch_desc->num_typec_switches = typec_mode_switch_node_count(port); > + if (!switch_desc->num_typec_switches) { > + dev_dbg(dev, "No Type-C switches node found\n"); > + return 0; > + } > + > + switch_desc->typec_ports = devm_kcalloc(dev, switch_desc->num_typec_switches, > + sizeof(struct drm_dp_typec_port_data), > + GFP_KERNEL); > + if (!switch_desc->typec_ports) > + return -ENOMEM; > + > + /* Register switches for each connector. */ > + for_each_typec_mode_switch_node(port, sw) { > + ret = drm_dp_register_mode_switch(dev, sw, switch_desc, data, mux_set); > + if (ret) > + goto err_unregister_typec_switches; > + } > + > + return 0; > + > +err_unregister_typec_switches: > + fwnode_handle_put(sw); > + drm_dp_unregister_typec_switches(switch_desc); > + return ret; > +} > +EXPORT_SYMBOL(drm_dp_register_typec_switches); > + > +/** > + * drm_dp_unregister_typec_switches() - unregister Type-C switches > + * @switch_desc: A Type-C switch descriptor > + */ > +void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc) > +{ > + unsigned int i; > + > + for (i = 0; i < switch_desc->num_typec_switches; i++) > + typec_mux_unregister(switch_desc->typec_ports[i].typec_mux); > +} > +EXPORT_SYMBOL(drm_dp_unregister_typec_switches); > diff --git a/include/drm/display/drm_dp_helper.h b/include/drm/display/drm_dp_helper.h > index ab55453f2d2c..0fe56586d7bc 100644 > --- a/include/drm/display/drm_dp_helper.h > +++ b/include/drm/display/drm_dp_helper.h > @@ -25,6 +25,7 @@ > > #include <linux/delay.h> > #include <linux/i2c.h> > +#include <linux/usb/typec_mux.h> > > #include <drm/display/drm_dp.h> > #include <drm/drm_connector.h> > @@ -763,4 +764,49 @@ bool drm_dp_downstream_rgb_to_ycbcr_conversion(const u8 dpcd[DP_RECEIVER_CAP_SIZ > const u8 port_cap[4], u8 color_spc); > int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8 color_spc); > > +struct drm_dp_typec_port_data { > + struct typec_mux_dev *typec_mux; > + int port_num; > + struct fwnode_handle *fwnode; > + void *data; > +}; > + > +struct drm_dp_typec_switch_desc { > + int num_typec_switches; > + struct drm_dp_typec_port_data *typec_ports; > +}; > + > +#define for_each_typec_mode_switch_node(port, sw) \ > + fwnode_for_each_child_node((port), (sw)) \ > + for_each_if(fwnode_property_present((sw), "mode-switch")) > + > +static inline unsigned int typec_mode_switch_node_count(struct fwnode_handle *port) > +{ > + struct fwnode_handle *sw; > + unsigned int count = 0; > + > + for_each_typec_mode_switch_node(port, sw) > + count++; > + > + return count; > +} > + > +#ifdef CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER > +void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc); > +int drm_dp_register_typec_switches(struct device *dev, struct fwnode_handle *port, > + struct drm_dp_typec_switch_desc *switch_desc, > + void *data, typec_mux_set_fn_t mux_set); > +#else > +static inline void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc) > +{ > +} > +static inline int drm_dp_register_typec_switches( > + struct device *dev, struct fwnode_handle *port, > + struct drm_dp_typec_switch_desc *switch_desc, void *data, > + typec_mux_set_fn_t mux_set) > +{ > + return -EOPNOTSUPP; > +} > +#endif > + > #endif /* _DRM_DP_HELPER_H_ */ > -- > 2.40.0.rc1.284.g88254d51c5-goog >
On Wed, Mar 22, 2023 at 06:27:56PM +0200, Jani Nikula wrote: > On Wed, 22 Mar 2023, Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote: > > On Wed, Mar 22, 2023 at 06:46:32PM +0800, Pin-yen Lin wrote: > >> +#ifdef CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER > > > > Ah, maybe this should use IS_REACHABLE() ? > > Personally, I think IS_REACHABLE() is a build-time band-aid solution to > a problem that should be solved in Kconfig. :p > > I think it always means there's a configuration combo that shouldn't > exist, and it's a surprise to the user when they've configured > something, Kconfig has deemed it a valid configuration, but they don't > get the feature they want. > > As a user, how would they even debug that case? Double check configs, > don't see anything wrong. Usual pairing is 'imply FOO' in Kconfig & 'IS_REACHEABLE(CONFIG_FOO)' in the code. And I believe it's not an abnormal.
On Thu, Mar 23, 2023 at 12:38:49AM +0200, Dmitry Baryshkov wrote: > On Wed, 22 Mar 2023 at 12:47, Pin-yen Lin <treapking@chromium.org> wrote: ... > > +config DRM_DISPLAY_DP_TYPEC_HELPER > > + bool > > + default y > > + depends on DRM_DISPLAY_HELPER > > + depends on DRM_DISPLAY_HELPER=TYPEC || TYPEC=y > > If it is a select'able option, it doesn't make sense to use "depends" > here. Select will override depends. He-he, not so easy. This will help to find configurations that miss these dependencies. Arnd taught me that. IIRC the ASoC subsystem has a lot of such cases. > > + help > > + DRM display helpers for USB Type-C Displayport Alternate mode.
Hi Andy, Thanks for the review. On Wed, Mar 22, 2023 at 8:01 PM Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote: > > On Wed, Mar 22, 2023 at 06:46:32PM +0800, Pin-yen Lin wrote: > > Add helpers to register and unregister Type-C "switches" for bridges > > capable of switching their output between two downstream devices. > > > > The helper registers USB Type-C mode switches when the "mode-switch" > > and the "reg" properties are available in Device Tree. > > ... > > > +config DRM_DISPLAY_DP_TYPEC_HELPER > > > + bool > > + default y > > def_bool y > > > + depends on DRM_DISPLAY_HELPER > > + depends on DRM_DISPLAY_HELPER=TYPEC || TYPEC=y > > + help > > + DRM display helpers for USB Type-C Displayport Alternate mode. > > Hmm... Dunno if this help is enough. Okay I'll add more detail in the next version. > > ... > > > + snprintf(name, sizeof(name), "%pfwP-%u", fwnode, port_num); > > Would it be possible to have a dup in name and would it be a problem if so? > The port_num is included in the name, so the names should be unique. Also, the fwnode name actually contains the reg property, so this name looks like "endpoint@0-1" now... I'll change the name from fwnode name to dev_name() per Dmitry's comment. > ... > > > +/** > > + * drm_dp_register_typec_switches() - register Type-C switches > > + * @dev: Device that registers Type-C switches > > + * @port: Device node for the switch > > + * @switch_desc: A Type-C switch descriptor > > + * @data: Private data for the switches > > + * @mux_set: Callback function for typec_mux_set > > + * > > + * This function registers USB Type-C switches for DP bridges that can switch > > + * the output signal between their output pins. This function uses devm_kcalloc > > + * to allocate memory, so it is expected to only call this in the driver probe > > + * functions. > > + * > > + * Currently only mode switches are implemented, and the function assumes the > > + * given @port device node has endpoints with "mode-switch" property. > > + * The port number is determined by the "reg" property of the endpoint. > > `kernel-doc -v ...` should complain on absence of "Return" section. > > > + */ > > ... > > > + switch_desc->typec_ports = devm_kcalloc(dev, switch_desc->num_typec_switches, > > + sizeof(struct drm_dp_typec_port_data), > > sizeof(*switch_desc_typec_ports), > > ? > > > + GFP_KERNEL); > > + if (!switch_desc->typec_ports) > > + return -ENOMEM; > > ... > > > +#ifdef CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER > > Ah, maybe this should use IS_REACHABLE() ? CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER is a boolean. Is there any difference between IS_REACHABLE and ifdef when the given config is a boolean? > > > +void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc); > > +int drm_dp_register_typec_switches(struct device *dev, struct fwnode_handle *port, > > + struct drm_dp_typec_switch_desc *switch_desc, > > + void *data, typec_mux_set_fn_t mux_set); > > +#else > > +static inline void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc) > > +{ > > +} > > +static inline int drm_dp_register_typec_switches( > > + struct device *dev, struct fwnode_handle *port, > > + struct drm_dp_typec_switch_desc *switch_desc, void *data, > > + typec_mux_set_fn_t mux_set) > > +{ > > + return -EOPNOTSUPP; > > +} > > +#endif > > -- > With Best Regards, > Andy Shevchenko > Best regards, Pin-yen >
Hi Dmitry, Thanks for the review. On Thu, Mar 23, 2023 at 7:39 AM Dmitry Baryshkov <dmitry.baryshkov@linaro.org> wrote: > > On Wed, 22 Mar 2023 at 12:47, Pin-yen Lin <treapking@chromium.org> wrote: > > > > Add helpers to register and unregister Type-C "switches" for bridges > > capable of switching their output between two downstream devices. > > > > The helper registers USB Type-C mode switches when the "mode-switch" > > and the "reg" properties are available in Device Tree. > > > > Signed-off-by: Pin-yen Lin <treapking@chromium.org> > > > > --- > > > > Changes in v14: > > - Introduce a new Kconfig becuase it didn't build when CONFIG_TYPEC=m > > - Add comments about devm_* usage > > - Fix style issues > > > > Changes in v13: > > - Add typec_mode_switch_node_count helper > > - Fix style issues > > > > Changes in v12: > > - Add fwnode_for_each_typec_mode_switch macro > > - Remove a duplicated dmesg in the helper > > - Used IS_REACHABLE instead to guard the function signatures > > > > Changes in v11: > > - Use fwnode helpers instead of DT > > - Moved the helpers to a new file > > - Use "reg" instead of "data-lanes" to determine the port number > > - Dropped collected tags due to new changes > > > > Changes in v10: > > - Collected Reviewed-by and Tested-by tags > > - Replaced "void *" with "typec_mux_set_fn_t" for mux_set callbacks > > - Print out the node name when errors on parsing DT > > - Use dev_dbg instead of dev_warn when no Type-C switch nodes available > > - Made the return path of drm_dp_register_mode_switch clearer > > > > Changes in v8: > > - Fixed the build issue when CONFIG_TYPEC=m > > - Fixed some style issues > > > > Changes in v7: > > - Extracted the common codes to a helper function > > - New in v7 > > > > drivers/gpu/drm/display/Kconfig | 8 ++ > > drivers/gpu/drm/display/Makefile | 2 + > > drivers/gpu/drm/display/drm_dp_typec_helper.c | 105 ++++++++++++++++++ > > include/drm/display/drm_dp_helper.h | 46 ++++++++ > > 4 files changed, 161 insertions(+) > > create mode 100644 drivers/gpu/drm/display/drm_dp_typec_helper.c > > > > diff --git a/drivers/gpu/drm/display/Kconfig b/drivers/gpu/drm/display/Kconfig > > index 09712b88a5b8..d61076947a1c 100644 > > --- a/drivers/gpu/drm/display/Kconfig > > +++ b/drivers/gpu/drm/display/Kconfig > > @@ -29,6 +29,14 @@ config DRM_DISPLAY_HDMI_HELPER > > help > > DRM display helpers for HDMI. > > > > +config DRM_DISPLAY_DP_TYPEC_HELPER > > + bool > > + default y > > + depends on DRM_DISPLAY_HELPER > > + depends on DRM_DISPLAY_HELPER=TYPEC || TYPEC=y > > If it is a select'able option, it doesn't make sense to use "depends" > here. Select will override depends. > I'm not very familiar with the practices of Kconfigs, but I'll keep this in the next version per Andy's comment. > > + help > > + DRM display helpers for USB Type-C Displayport Alternate mode. > > + > > config DRM_DP_AUX_CHARDEV > > bool "DRM DP AUX Interface" > > depends on DRM && DRM_DISPLAY_HELPER > > diff --git a/drivers/gpu/drm/display/Makefile b/drivers/gpu/drm/display/Makefile > > index 17ac4a1006a8..2202a6aea38e 100644 > > --- a/drivers/gpu/drm/display/Makefile > > +++ b/drivers/gpu/drm/display/Makefile > > @@ -8,6 +8,8 @@ drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_HELPER) += \ > > drm_dp_helper.o \ > > drm_dp_mst_topology.o \ > > drm_dsc_helper.o > > +drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER) += \ > > + drm_dp_typec_helper.o > > drm_display_helper-$(CONFIG_DRM_DISPLAY_HDCP_HELPER) += drm_hdcp_helper.o > > drm_display_helper-$(CONFIG_DRM_DISPLAY_HDMI_HELPER) += \ > > drm_hdmi_helper.o \ > > diff --git a/drivers/gpu/drm/display/drm_dp_typec_helper.c b/drivers/gpu/drm/display/drm_dp_typec_helper.c > > new file mode 100644 > > index 000000000000..1562a9ccdaf2 > > --- /dev/null > > +++ b/drivers/gpu/drm/display/drm_dp_typec_helper.c > > @@ -0,0 +1,105 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > + > > +#include <linux/usb/typec_mux.h> > > +#include <drm/display/drm_dp_helper.h> > > + > > +static int drm_dp_register_mode_switch(struct device *dev, > > + struct fwnode_handle *fwnode, > > + struct drm_dp_typec_switch_desc *switch_desc, > > + void *data, typec_mux_set_fn_t mux_set) > > +{ > > + struct drm_dp_typec_port_data *port_data; > > + struct typec_mux_desc mux_desc = {}; > > + char name[32]; > > Why 32? This is just a random length that is probably sufficiently large. I see other users use the pointer from `fwnode_get_name` directly, but we want to append the port number to ensure the names are unique. > > > + u32 port_num; > > + int ret; > > + > > + ret = fwnode_property_read_u32(fwnode, "reg", &port_num); > > + if (ret) { > > + dev_err(dev, "Failed to read reg property: %d\n", ret); > > + return ret; > > + } > > + > > + port_data = &switch_desc->typec_ports[port_num]; > > + port_data->data = data; > > + port_data->port_num = port_num; > > + port_data->fwnode = fwnode; > > + mux_desc.fwnode = fwnode; > > + mux_desc.drvdata = port_data; > > + snprintf(name, sizeof(name), "%pfwP-%u", fwnode, port_num); > > I think it makes more sense to use dev_name here instead of fwnode. Thanks for the suggestions. I'll update this in the next version. > > > + mux_desc.name = name; > > + mux_desc.set = mux_set; > > + > > + port_data->typec_mux = typec_mux_register(dev, &mux_desc); > > + ret = PTR_ERR_OR_ZERO(port_data->typec_mux); > > + if (ret) > > + dev_err(dev, "Mode switch register for port %d failed: %d\n", > > + port_num, ret); > > + > > + return ret; > > +} > > + > > +/** > > + * drm_dp_register_typec_switches() - register Type-C switches > > + * @dev: Device that registers Type-C switches > > + * @port: Device node for the switch > > + * @switch_desc: A Type-C switch descriptor > > + * @data: Private data for the switches > > + * @mux_set: Callback function for typec_mux_set > > + * > > + * This function registers USB Type-C switches for DP bridges that can switch > > + * the output signal between their output pins. This function uses devm_kcalloc > > + * to allocate memory, so it is expected to only call this in the driver probe > > + * functions. > > + * > > + * Currently only mode switches are implemented, and the function assumes the > > + * given @port device node has endpoints with "mode-switch" property. > > + * The port number is determined by the "reg" property of the endpoint. > > + */ > > +int drm_dp_register_typec_switches(struct device *dev, struct fwnode_handle *port, > > + struct drm_dp_typec_switch_desc *switch_desc, > > + void *data, typec_mux_set_fn_t mux_set) > > +{ > > + struct fwnode_handle *sw; > > + int ret; > > + > > + switch_desc->num_typec_switches = typec_mode_switch_node_count(port); > > + if (!switch_desc->num_typec_switches) { > > + dev_dbg(dev, "No Type-C switches node found\n"); > > + return 0; > > + } > > + > > + switch_desc->typec_ports = devm_kcalloc(dev, switch_desc->num_typec_switches, > > + sizeof(struct drm_dp_typec_port_data), > > + GFP_KERNEL); > > + if (!switch_desc->typec_ports) > > + return -ENOMEM; > > + > > + /* Register switches for each connector. */ > > + for_each_typec_mode_switch_node(port, sw) { > > + ret = drm_dp_register_mode_switch(dev, sw, switch_desc, data, mux_set); > > + if (ret) > > + goto err_unregister_typec_switches; > > + } > > + > > + return 0; > > + > > +err_unregister_typec_switches: > > + fwnode_handle_put(sw); > > + drm_dp_unregister_typec_switches(switch_desc); > > + return ret; > > +} > > +EXPORT_SYMBOL(drm_dp_register_typec_switches); > > + > > +/** > > + * drm_dp_unregister_typec_switches() - unregister Type-C switches > > + * @switch_desc: A Type-C switch descriptor > > + */ > > +void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc) > > +{ > > + unsigned int i; > > + > > + for (i = 0; i < switch_desc->num_typec_switches; i++) > > + typec_mux_unregister(switch_desc->typec_ports[i].typec_mux); > > +} > > +EXPORT_SYMBOL(drm_dp_unregister_typec_switches); > > diff --git a/include/drm/display/drm_dp_helper.h b/include/drm/display/drm_dp_helper.h > > index ab55453f2d2c..0fe56586d7bc 100644 > > --- a/include/drm/display/drm_dp_helper.h > > +++ b/include/drm/display/drm_dp_helper.h > > @@ -25,6 +25,7 @@ > > > > #include <linux/delay.h> > > #include <linux/i2c.h> > > +#include <linux/usb/typec_mux.h> > > > > #include <drm/display/drm_dp.h> > > #include <drm/drm_connector.h> > > @@ -763,4 +764,49 @@ bool drm_dp_downstream_rgb_to_ycbcr_conversion(const u8 dpcd[DP_RECEIVER_CAP_SIZ > > const u8 port_cap[4], u8 color_spc); > > int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8 color_spc); > > > > +struct drm_dp_typec_port_data { > > + struct typec_mux_dev *typec_mux; > > + int port_num; > > + struct fwnode_handle *fwnode; > > + void *data; > > +}; > > + > > +struct drm_dp_typec_switch_desc { > > + int num_typec_switches; > > + struct drm_dp_typec_port_data *typec_ports; > > +}; > > + > > +#define for_each_typec_mode_switch_node(port, sw) \ > > + fwnode_for_each_child_node((port), (sw)) \ > > + for_each_if(fwnode_property_present((sw), "mode-switch")) > > + > > +static inline unsigned int typec_mode_switch_node_count(struct fwnode_handle *port) > > +{ > > + struct fwnode_handle *sw; > > + unsigned int count = 0; > > + > > + for_each_typec_mode_switch_node(port, sw) > > + count++; > > + > > + return count; > > +} > > + > > +#ifdef CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER > > +void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc); > > +int drm_dp_register_typec_switches(struct device *dev, struct fwnode_handle *port, > > + struct drm_dp_typec_switch_desc *switch_desc, > > + void *data, typec_mux_set_fn_t mux_set); > > +#else > > +static inline void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc) > > +{ > > +} > > +static inline int drm_dp_register_typec_switches( > > + struct device *dev, struct fwnode_handle *port, > > + struct drm_dp_typec_switch_desc *switch_desc, void *data, > > + typec_mux_set_fn_t mux_set) > > +{ > > + return -EOPNOTSUPP; > > +} > > +#endif > > + > > #endif /* _DRM_DP_HELPER_H_ */ > > -- > > 2.40.0.rc1.284.g88254d51c5-goog > > > > > -- > With best wishes > Dmitry Best regards, Pin-yen
On Fri, Mar 31, 2023 at 11:36 AM Pin-yen Lin <treapking@chromium.org> wrote: > > Hi Andy, > > Thanks for the review. > > On Wed, Mar 22, 2023 at 8:01 PM Andy Shevchenko > <andriy.shevchenko@linux.intel.com> wrote: > > > > On Wed, Mar 22, 2023 at 06:46:32PM +0800, Pin-yen Lin wrote: > > > Add helpers to register and unregister Type-C "switches" for bridges > > > capable of switching their output between two downstream devices. > > > > > > The helper registers USB Type-C mode switches when the "mode-switch" > > > and the "reg" properties are available in Device Tree. > > > > ... > > > > > +config DRM_DISPLAY_DP_TYPEC_HELPER > > > > > + bool > > > + default y > > > > def_bool y > > > > > + depends on DRM_DISPLAY_HELPER > > > + depends on DRM_DISPLAY_HELPER=TYPEC || TYPEC=y > > > + help > > > + DRM display helpers for USB Type-C Displayport Alternate mode. > > > > Hmm... Dunno if this help is enough. > > Okay I'll add more detail in the next version. > > > > ... > > > > > + snprintf(name, sizeof(name), "%pfwP-%u", fwnode, port_num); > > > > Would it be possible to have a dup in name and would it be a problem if so? > > > The port_num is included in the name, so the names should be unique. > Also, the fwnode name actually contains the reg property, so this name > looks like "endpoint@0-1" now... I'll change the name from fwnode name This should be "endpoint@0-0", or "endpoint@1-1@. The `port_num` value has the same number as the `reg` property > to dev_name() per Dmitry's comment. > > ... > > > > > +/** > > > + * drm_dp_register_typec_switches() - register Type-C switches > > > + * @dev: Device that registers Type-C switches > > > + * @port: Device node for the switch > > > + * @switch_desc: A Type-C switch descriptor > > > + * @data: Private data for the switches > > > + * @mux_set: Callback function for typec_mux_set > > > + * > > > + * This function registers USB Type-C switches for DP bridges that can switch > > > + * the output signal between their output pins. This function uses devm_kcalloc > > > + * to allocate memory, so it is expected to only call this in the driver probe > > > + * functions. > > > + * > > > + * Currently only mode switches are implemented, and the function assumes the > > > + * given @port device node has endpoints with "mode-switch" property. > > > + * The port number is determined by the "reg" property of the endpoint. > > > > `kernel-doc -v ...` should complain on absence of "Return" section. > > > > > + */ > > > > ... > > > > > + switch_desc->typec_ports = devm_kcalloc(dev, switch_desc->num_typec_switches, > > > + sizeof(struct drm_dp_typec_port_data), > > > > sizeof(*switch_desc_typec_ports), > > > > ? > > > > > + GFP_KERNEL); > > > + if (!switch_desc->typec_ports) > > > + return -ENOMEM; > > > > ... > > > > > +#ifdef CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER > > > > Ah, maybe this should use IS_REACHABLE() ? > > CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER is a boolean. Is there any > difference between IS_REACHABLE and ifdef when the given config is a > boolean? > > > > > +void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc); > > > +int drm_dp_register_typec_switches(struct device *dev, struct fwnode_handle *port, > > > + struct drm_dp_typec_switch_desc *switch_desc, > > > + void *data, typec_mux_set_fn_t mux_set); > > > +#else > > > +static inline void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc) > > > +{ > > > +} > > > +static inline int drm_dp_register_typec_switches( > > > + struct device *dev, struct fwnode_handle *port, > > > + struct drm_dp_typec_switch_desc *switch_desc, void *data, > > > + typec_mux_set_fn_t mux_set) > > > +{ > > > + return -EOPNOTSUPP; > > > +} > > > +#endif > > > > -- > > With Best Regards, > > Andy Shevchenko > > > > Best regards, > Pin-yen > >
Hi Andy, Thanks for the review. On Wed, Mar 22, 2023 at 8:16 PM Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote: > > On Wed, Mar 22, 2023 at 06:46:36PM +0800, Pin-yen Lin wrote: > > Register USB Type-C mode switches when the "mode-switch" property and > > relevant ports are available in Device Tree. Configure the crosspoint > > switch based on the entered alternate mode for a specific Type-C > > connector. > > > > Crosspoint switch can also be used for switching the output signal for > > different orientations of a single USB Type-C connector, but the > > orientation switch is not implemented yet. A TODO is added for this. > > ... > > > +static int anx7625_typec_mux_set(struct typec_mux_dev *mux, > > + struct typec_mux_state *state) > > +{ > > + struct drm_dp_typec_port_data *port = typec_mux_get_drvdata(mux); > > + struct anx7625_data *ctx = port->data; > > + struct device *dev = ctx->dev; > > + struct drm_dp_typec_switch_desc switch_desc = ctx->switch_desc; > > + bool new_dp_connected, old_dp_connected; > > + > > + if (switch_desc.num_typec_switches == 1) > > + return 0; > > > + wait_for_completion(&ctx->mux_register); > > How do we guarantee this won't become an infinite waiting? > Perhaps a comment explaining that? > > > + old_dp_connected = ctx->port_data[0].dp_connected || > > + ctx->port_data[1].dp_connected; > > + > > + ctx->port_data[port->port_num].dp_connected = > > + state->alt && > > + state->alt->svid == USB_TYPEC_DP_SID && > > + state->alt->mode == USB_TYPEC_DP_MODE; > > + > > + dev_dbg(dev, "mux_set dp_connected: c0=%d, c1=%d\n", > > + ctx->port_data[0].dp_connected, ctx->port_data[1].dp_connected); > > + > > + new_dp_connected = ctx->port_data[0].dp_connected || > > + ctx->port_data[1].dp_connected; > > + > > + /* DP on, power on first */ > > + if (!old_dp_connected && new_dp_connected) > > + pm_runtime_get_sync(dev); > > + > > + anx7625_typec_two_ports_update(ctx); > > + > > + /* DP off, power off last */ > > + if (old_dp_connected && !new_dp_connected) > > + pm_runtime_put_sync(dev); > > + > > + return 0; > > +} > > ... > > > + struct device_node *port_node = of_graph_get_port_by_id(dev->of_node, 1); > > You use fwnode below, so why not fwnode_graph_...(dev_fwnode(dev), ...) ? There is no existing helper like `fwnode_graph_get_port_by_id`, so using of_graph variant is easier here. Should I add a `fwnode_graph_get_port_by_id` helper for this? > > > + struct drm_dp_typec_switch_desc *switch_desc = &ctx->switch_desc; > > + int ret; > > + u32 dp_lanes[4]; > > + unsigned int i, num_lanes; > > + > > + /* > > + * Currently, only mode switch is implemented. > > + * TODO: Implement Type-C orientation switch for anx7625. > > + */ > > + ret = drm_dp_register_typec_switches(dev, &port_node->fwnode, > > + &ctx->switch_desc, ctx, > > + anx7625_typec_mux_set); > > + if (ret) > > + return ret; > > + > > + ctx->port_data = devm_kcalloc(dev, switch_desc->num_typec_switches, > > + sizeof(struct anx7625_typec_port_data), > > sizeof(*ctx->port_data), > > ? > > > + GFP_KERNEL); > > + if (!ctx->port_data) { > > + ret = -ENOMEM; > > + goto unregister_mux; > > + } > > ... > > > +struct anx7625_typec_port_data { > > + bool dp_connected; > > + enum typec_orientation orientation; > > Most likely enum will be 32-bit and bool 8-bit. Which means that the data type > size become 8 bytes for no reason. Can you swap the lines and perhaps check this > with `pahole` tool? > > > +}; > > -- > With Best Regards, > Andy Shevchenko > > Best regards, Pin-yen